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What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
...t's restrict the discussion to the plain IEnumerable LINQ-to-Objects provider. Further, let's assume that any Func passed in as a selector / mutator / etc. is a cheap O(1) operation.
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What is the difference between JDK dynamic proxy and CGLib?
...t would stop these libraries from allowing to subclass your class and override your methods.
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Why does the C# compiler not fault code where a static method calls an instance method?
...7.3 (May 2018). In What's new in C# 7.3, the section Improved overload candidates, item 1, it is explained how the overload resolution rules have changed so that non-static overloads are discarded early. So the below answer (and this entire question) has mostly only historical interest by now!
(P...
Referencing a string in a string array resource with xml
...an, but there seems to be a workaround:.
If you take a look into the Android Resource here:
http://developer.android.com/guide/topics/resources/string-resource.html
You see than under the array section (string array, at least), the "RESOURCE REFERENCE" (as you get from an XML) does not specify a ...
How do RVM and rbenv actually work?
...ng. Every time you install a new version of Ruby or install a gem that provides a command, run rbenv rehash to make sure any new commands are shimmed.
These shims live in a single directory (~/.rbenv/shims by default). To use rbenv, you need only add the shims directory to the front of your PATH:
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Can I make a function available in every controller in angular?
...e a utility function foo that I want to be able to call from anywhere inside of my ng-app declaration. Is there someway I can make it globally accessible in my module setup or do I need to add it to the scope in every controller?
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what is the difference between a portlet and a servlet?
...only through the portal page
which holds the portlet.
Portlets can be provided with controls to manipulate its window states
or portlet modes.
Multiple instances of a single portlet can be placed onto the same
page.
Portlets support persistent configuration and customization, profile
information....
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...pecially since your data are already factored, you can use complete from "tidyr" to get what you might be looking for:
library(tidyr)
df %>%
group_by(b) %>%
summarise(count_a=length(a)) %>%
complete(b)
# Source: local data frame [3 x 2]
#
# b count_a
# (fctr) (int)
# 1 ...
Why not use exceptions as regular flow of control?
To avoid all standard-answers I could have Googled on, I will provide an example you all can attack at will.
24 Answers
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Boolean operators && and ||
...ing). For example, here's a comparison using an undefined value a; if it didn't short-circuit, as & and | don't, it would give an error.
a
# Error: object 'a' not found
TRUE || a
# [1] TRUE
FALSE && a
# [1] FALSE
TRUE | a
# Error: object 'a' not found
FALSE & a
# Error: object 'a' ...